A method of controlling an electric motor of a vehicle includes monitoring torque command signals from a vehicle system to the electric motor, each torque command signal configured to cause the electric motor to output a commanded torque, and monitoring a speed of the vehicle and an output torque of the electric motor, the output torque responsive to a drive signal generated based on the torque command signals. The method also includes, based on the output torque and the vehicle speed indicating a low motor efficiency condition, modulating the drive signal between a first torque value and a second torque value that is less than the first torque value, the first torque value greater than the commanded torque and selected to increase an efficiency of the electric motor.